Photos of Kunming Airlines flight attendants in overhead lockers in China has caused outrage on the country's social media

Female cabin crew members were forced into overhead lockers on a plane as part of an initiation ritual for a Chinese airline, according to social media in China.

The images of the flight attendants lying in the lockers were shared on WeChat, a Chinese social media and texting app, and have angered Chinese internet users, known as netizens.

A post on WeChat said cabin crew were "forced into lockers by security staff upon completing 30 to 50 hours of service" as part of an "industry ritual", according to the BBC.

The carrier, Kunming Airlines, has issued a statement saying it is investigating the incident, adding that the crew had completed their duties and that the safety of the flight was not affected.

"The company attaches high importance to this incident and will prevent such things from happening again," the statement, reported by the BBC, said.

The Chinese state news organisation, CCTVNews, reported that the stewardesses uploaded the images after growing unrest about the airline rituals.

It said that the female cabin crew members forced into the lockers by male colleagues "went through with it in fear of being edged out by other colleagues". "A few stewardesses were labelled 'asocial' and 'cocky' after they refused the ritual," CCTVNews said in a Facebook post.

It reported that cabin crew had filed numerous complaints over a number of years, however they were not taken seriously.

Stuffing cabin crew members into overhead lockers is apparently a common occurrence in airlines around the world.

One netizen, @Jiuaigaimingziyaowoa, said: "Being a trend overseas doesn't mean it can be accepted in China as well. 'Popular' is not equal to 'right'."

Another, @Beimingyouyu, said: "I’m more concerned about the fact that the company claimed to not know a thing about the ritual. If it knows nothing about its employees for five years, how can we expect them to know anything about the customers?"

Last year a picture emerged on Twitter purporting to show cabin crew from Emirates in overhead lockers, however, these staff members were smiling and posing.